0


用少量光循环光脉冲跟踪生物分子中的主要光致事件

Tracking primary photoinduced events in biomolecules with few-optical-cycle light pulses
课程网址: http://videolectures.net/kolokviji_cerullo_tppe/  
主讲教师: Giulio Cerullo
开课单位: 米兰理工学院
开课时间: 2009-09-21
课程语种: 英语
中文简介:
有机分子中的许多光诱导过程,例如能量弛豫,能量/电荷转移和构象变化,发生在超快时间尺度上,范围从10-14到10-12s。这些基本过程的速度与其效率密切相关,使超快光学光谱成为他们研究的宝贵工具。泵浦探测光谱法需要短脉冲,以便观察快速动态和宽频率可调性,以激发系统在谐振和探测在不同频率发生的光学跃迁。光参量放大器(OPA)是此类实验的理想工具,因为它们提供频率可调性并支持宽增益带宽,从而可以生成非常短的脉冲。在本次演讲中,我将描述一种基于两个同步OPA的现有技术系统,在400 nm至1.5 mm的非常宽的光谱范围内提供低于20 fs的时间分辨率。在回顾了脉冲生成技术和系统性能之后,我将介绍一些应用实例,例如:光合光采集复合物中的能量转移,碳纳米管中的电子和振动动力学,视紫红质的异构化。
课程简介: Many light-induced processes in organic molecules, such as energy relaxation, energy/charge transfer and conformational changes, occur on ultrafast timescales, ranging from 10-14 to 10-12 s. The speed of such elementary processes is intimately linked to their efficiency, making ultrafast optical spectroscopy an invaluable tool for their investigation. Pump-probe spectroscopy requires both short pulses, in order to observe fast dynamics, and broad frequency tunability, to excite a system on resonance and probe optical transitions occurring at different frequencies. Optical parametric amplifiers (OPAs) are ideal tools for such experiments, because they provide frequency tunability and support broad gain bandwidths, enabling the generation of very short pulses. In this talk I will describe a state of the art system, based on two synchronized OPAs, providing sub-20-fs temporal resolution over a very broad spectral range, from 400 nm to 1.5 mm. After reviewing the pulse generation techniques and the system performance, I will present selected examples of applications, such as: energy transfer in photosynthetic light harvesting complexes, electronic and vibrational dynamics in carbon nanotubes, isomerization of rhodopsin.
关 键 词: 光诱导; 光参量放大器; 脉冲生成技术
课程来源: 视频讲座网
最后编审: 2019-05-12:cjy
阅读次数: 44